An automatic applicator for liquid pharmaceutical preparations, in particular for insulin, more particularly for an application of multiple injections of established doses of a medicine from an interchangeable container, comprising a body housing (1) connected to a housing (2) of an interchangeable container with a medicine, in particular insulin, having a piston (12), suitable for expelling the medicine, said piston being displaced only linearly by means of an integrated drive unit, suitable for immobilizing, moving, directing linearly and block the rotation of said piston (12), moved by means of a double acting clutch, by means of a tension spring (15) located in the body housing (1), said spring tensioned by means of a ring Rotary (3) of manual dose setting by means of the same double-acting clutch unit, in which said drive unit is activated by means of an activation unit (13) and a dose is indicated by means of an indication arrangement, characterized in that it comprises at least one locking pin (5.6) placed on top of the ratchet tube (5), collaborating with at least one pin (1.3) placed in the inner part of the housing (1) of cylindrical body.Un aplicador automático para preparaciones farmacéuticas líquidas, en particular para insulina, más en particular para una aplicación de múltiples inyecciones de dosis establecidas de una medicina procedentes de un envase intercambiable, que comprende un alojamiento (1) de cuerpo conectado a un alojamiento (2) de un envase intercambiable con una medicina, en particular insulina, que tiene un émbolo (12), adecuado para expulsar la medicina, siendo desplazado dicho émbolo únicamente de forma lineal por medio de una unidad de accionamiento integrada, adecuada para inmovilizar, mover, dirigir linealmente y bloquear la rotación de dicho émbolo (12), movido por medio de un embrague de doble acción, por medio de un resorte (15) de tensión situado en el alojamiento (1) de cuerpo, tensado dicho resorte por medio de un anillo girat
